DESIGNED MONOMERS AND POLYMERS
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2019
·
IF 1.528
Meng-Di Chen,Guo Zhang,Shi-Chang Chen,Xian-Ming Zhang,Wen-Xing Chen
In this study, 9-anthracenemethyl methacrylate (AMMA) and styrene (St) as monomers and benzoyl peroxide as an initiator were used to synthesize P(St-co-AMMA), a macromolecule tracer with a fluorescence effect, via free radical copolymerization. A fluorescent online detection device was built on the basis of the principle of fluorescence online detection by using the single-screw extrusion platform of a torque rheometer to explore the effect of the amount of macromolecular tracer and screw speed on the residence time distribution of polystyrene in single-screw extrusion. Fourier transform infrared spectroscopy, 1H-NMR, thermal stability, fluorescence properties, and rheological properties show that the resulting product P(St-co-AMMA) has a degree of thermal stability, fluorescence, and rheological properties similar to polystyrene, so this product can be used to characterize the residence time distribution during single-screw extrusion. The amount of macromolecular tracer P(St-co-AMMA) does not affect the residence time distribution of polystyrene during single-screw extrusion processing, meanwhile, the minimum residence time decreases and the residence time distribution becomes narrow as the screw speed increases, that is, the axial mixing capacity of the single-screw extruder decreases as the screw speed increases.
研究领域:
高分子化学
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材料科学
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聚合物加工工程
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产品关联
DOI
PubMed
高影响因子
JOURNAL OF APPLIED POLYMER SCIENCE
·
2018
·Vol. 135
·期 32
·46579
·
IF 1.901
Xie Li,Wei Li,Zhiqing Liu,Xiaolin Wang,Heling Guo,Rongjie Wang,Xuhong Guo,Cuihua Li,Xin Jia
Polyurethane (PU) has been widely used as a glue in various areas. However, adhesion in the presence of water is greatly impeded and results in most synthetic adhesive failure. In this study, we designed and synthesized a novel PU construction; underwater PU adhesives were created by the incorporation of synthetic glycerol monomethacrylate (GMA). Furthermore, the urethane structure helped the adhesive eliminate the interfacial water barrier through interactions that were stronger than hydrogen bonding, and GMA as a crosslinking agent was used to generate post-covalent-crosslinking networks through radical polymerization. This enhanced the cohesion so the diffusion of water molecules could be overcome. Fourier transform infrared spectroscopy, thermogravimetric analysis, underwater adhesion measurements, and tensile tests were used to characterize the chemical and mechanical properties of the as-obtained adhesive. This led to an adhesive with a better mechanical strength and interfacial adhesion in water, and the results show that the mechanical properties (tensile strength, Young's modulus, and tensile elongation) of the GMA–PU adhesive were higher than those of the pure PU. As for the 4% GMA, the tensile strength was enhanced by 24.3% and the elongation was enhanced by 125.23% over those of the pure PU. This confirmed that the incorporation of GMA into the PU matrix indeed induced increasing cohesion, and the sample's adhesive strength was 21.19 ± 3.9 MPa; this indicated a superior adhesive strength over that of the pure PU. In addition, we can foresee that underwater adhesion will play an important role in prospective surgery and engineering areas. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018 , 135 , 46579.
研究领域:
高分子材料
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生物医学工程
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粘附科学
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组织工程
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医用胶粘剂
✓ 已验证
DOI
高影响因子
POLYMER
·
2017
·
IF 3.684
Wei Yang,Xu Cheng,Haibo Wang,Yuansen Liu,Zongliang Du
Novel waterborne fluorinated polyurethane (WFPU) based on hydroxyl-terminated poly(fluoroalkyl methacrylates) (HTPFMA) was prepared successfully. The microstructures and micro-phase separation of WFPU were evaluated through infrared spectroscopy (FT-IR), X-ray diffraction (XRD), dynamic mechanical analysis (DMA), and scanning electron microscope (SEM). FT-IR revealed that the H-bonded carbonyl in hard domains increased with the increasing of fluorine content, resulting in enhancing the extent of micro-phase separation between hard and soft segments. XRD results indicated that the crystallinity of hard segment was enhanced with the increasing of fluorine content. The direct visual microstructures by SEM showed that the micro-phase separation was more significant when the fluorine content increased. DMA also revealed strengthened micro-phase separation with increasing fluorine content. The studies of mechanical properties confirmed that WFPU based on HTPFMA had outstanding mechanical properties. The effects of fluorine content on the static contact angles, surface free energy , and surface composition were also studied. The static contact angles of the WFPU films against water and methylene iodide reached around 108° and 84°, respectively. X-ray photoelectron spectroscopy (XPS) confirmed that the fluorine surface enrichment factor in the outermost 10 nm depth was about 10–18 fold higher than its bulk level.
研究领域:
高分子材料科学
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表面科学
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材料化学
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软物质物理
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功能涂层材料
✓ 已验证
DOI
高影响因子
MACROMOLECULAR CHEMISTRY AND PHYSICS
·
2019
·Vol. 220
·期 18
·1900299
·
IF 2.622
Huidong Yang,Hong Wang,Jingang Feng,Yumin Ye,Wenna Liu
Asymmetric divinyl monomers are attractive candidates for constructing functional polymer thin films owing to their ability to undergo further reactions after polymerization. Here, the first solventless synthesis of poly(allyl methacrylate) (PAMA) film with retention of abundant allyl groups using initiated chemical vapor deposition (iCVD) is reported. It is demonstrated that lower substrate and filament temperatures lead to better allyl retention, while higher temperatures lead to intramolecular cyclization. The retained allyl groups can be further crosslinked under UV light, and the crosslinking degree can be easily tuned by adjusting the exposure time. Patterning of iCVD PAMA films with 20 µm resolution using a TEM grid as photomask is also demonstrated. The reported synthesis method suggests possible solventless incorporation of AMA in thin films as a latent crosslinker or anchoring sites for further functionalization. The solventless patterning can also extend patterning technique to solvent-sensitive and non-planar substrates.
研究领域:
高分子材料科学
·
表面化学
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功能薄膜
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光响应材料
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生物医学工程
✓ 已验证
DOI
高影响因子